This invention relates to an improvement of the tone quality or timbre in a speaker device.
A boom in recent years among audiophiles or high-fidelity fans is so spectacular that the hearers or listeners have developed a sensitive ear. Speaker devices or other instruments in this field are required to be higher and higher in quality. For complying with the requirement for good timbre, all of the parts related to an audio apparatus as a whole, such as the tuner, the amplifier, the speaker device, etc., have to be generally elevated in quality as an entirety. It is not an exaggeration to say that the speaker device where an electric signal is finally converted into a sound (voice) is a key part for attaining the object of the timbre improvement.
The applicant of this invention earlier invented diaphragms or vibrating plates of extremely high rigidity made of a synthetic resin reinforced with fibers and a metallic material, etc. The previous invention has already been patented in the United States as U.S. Pat. No. 4,132,872.
Employment of such a diaphragm or vibration plate of high rigidity makes it possible, in comparison to that of a soft diaphragm made of paper or the like, to produce a highly clear sound and a sound volume comparable to that from a paper cone of nearly three times as large in diameter. And such a diaphragm of high rigidity is capable of producing a sound of broad range of compass covering the whole range of sound from high to low in a single diaphragm. Even such a remarkably improved speaker device still leaves something to be desired.